DIY Cree LED light

[Gomer]

I have this posted elsewhere, but I thought I'd cross post to RC as well for those of you that are interested.

The following is of a pure white light (not specific for a reef, although I contemplate using this in my BC14 with a pair of actinic bulbs).

The light uses 12x Cree XRE Q5 bin cool white emitters (I'd guess they are around 7000K), with CRS-W optics, a CPU heatsink, and xitanium 700mA CC drivers.



These LEDs put out about 185 lumens at 700mA and 3.6v or about 2.5watts each...or 30watts and 2220 lumens total




and now for the light in a tank photos LOL

IMPORTANT INFO!!!
This tank almost crashed recently. The corals look bleached cause they are. Fortunately, they are all still alive and I hope will all recover in time.

That said, here is the info!

Remember, this light is NOT setup for a reef (ie, I didn't include ANY blue LEDs. They are all "white".)

Photo set 1:

• All photos have the same color correction. The color shown is representative of the actual color in the tank
• All photos are shot with the SAME shutter speed, SAME iso, SAME balance, SAME 1/f. ie, you can DIRECTLY COMPARE.

Image guide:
Stock (1x10,000k, 1x50/50, 1xactinic) //// 1x10,000k only
1x 50/50 & 1x actinic //// no image
12x 700mA Cree XR-E Qbin @ 1" height //// @ 6" height






Photoset2:

• All photos have the same color correction. The color shown is representative of the actual color in the tank
• All photos are shot with the SAME iso, SAME balance, SAME 1/f but NOT the same shutter speed,. ie, you can NOT DIRECTLY COMPARE. You can however use shutter speeds to indirectly compare effective brightness (ie, how many 24watt PC bulbs it takes to equal the 30watt LED unit)
• The base image (1x24watt 10,000K bulb) is shot at 1/30sec.

Image Guide:
Stock (1x24watt 10k) 1/30sec //// 1/30 LED //// 1/40 LED
1/50 LED //// 1/60 LED //// 1/80 LED
1/100 LED //// 1/125 LED /// 1/160 LED


each LED is about 2.5watts for a total of 30watts

1/60=effective 1/2 LEDpower
1/120= effective 1/4 LED power

To my eyes, the intensity of the PC stock (1x24watt 10,000K) is about the same as the LED at 1/125sec. This is the same as saying, the LED light puts out about the same effective amount of light as 4x24watt 10K PC* By effective, I mean the amount of light that actually makes it TO the coral.

*Keep in mind that the LED is more like a MH and acts more like a point source, so the edges are darker and the center is brighter to that of the PC comparison.

[kcress]

Nicely done!

First useful comparison I've actually seen.

I'm impressed with the LED result showing the difference between 1" and 6" - not a lot of difference!

Do you know what angle lens those LED/lens systems have?

[philbo32]

Those LEDs look more like warm white than cool whites they look very yellow.

[philbo32]

This is my LED light box made from spotlight ultra-bright white/blue LEDs I have 9 spotlights which are placed in 3 lines of 3 in the box, I can control each line with timers and switches. Each LED spotlight gives off 18000 LUX at around 8" away which obviously will be much less under water. The LEDs run on 240V but only use 1.2 Watts per spotlight, each circuit uses less than 2 amps. I still need to add a moonlight which I hope to add soon, this will be a neon PC cathode mounted to the back of the light box. The light box is made from plywood;



Another pic showing the overall size of the box, it's mounted above the tank using plastic pipe frame work.



I used GU10 mains halogen type downlights (chrome fittings) but with cool white ultrabrite LED GU10 bulbs fitted instead of halogen, they are normally used in ceilings of kitchens or bathroms.

Fitting;



The box still needs painting.

[philbo32]

Originally posted by Gomer

Remember, this light is NOT setup for a reef (ie, I didn't include ANY blue LEDs. They are all "white".)

Most "white" LEDs in production today are modified blue LEDs: GaN-based, InGaN-active-layer LEDs emit blue light of wavelengths between 450 nm and 470 nm. This InGaN-GaN structure is covered with a yellowish phosphor coating usually made of cerium-doped yttrium aluminum garnet (Ce3+:YAG) crystals which have been powdered and bound in a type of viscous adhesive. The LED chip emits blue light, part of which is efficiently converted to a broad spectrum centered at about 580 nm (yellow) by the Ce3+:YAG. Since yellow light stimulates the red and green receptors of the eye, the resulting mix of blue and yellow light gives the appearance of white, the resulting shade often called "lunar white". This approach was developed by Nichia and has been used since 1996 for the manufacture of white LEDs.
http://en.wikipedia.org/wiki/Light-emitting_diode

So the white LEDs do contain a smal amount of blue and yelow light which can be clearly seen just below my light box where the light is reflected by the water even though they are cool white LEDs.

[Gomer]

Do you know what angle lens those LED/lens systems have?

They are 30deg (60deg full angle) optics)
http://www.ledil.fi/crs.pdf The CRS-W optics.

Those LEDs look more like warm white than cool whites they look very yellow.

When you are used to seeing tanks with actinic bulbs where a "yellow tank" is all 10,000k bulbs, even cool white will seem yellow to you. Warm white bulbs are lower then 5,000K like the incandecents in your house. This setup is most definately a cool white around 7,000K. Go ahead and put only a 6,700K bulb over your tank and behold how yellow it looks. We, the reefing community just prefer blue look.

"no blue ..etc etc"

What I ment by no blue, was no blue/actinic suplimentation. Every LED/Fluorescent system is suplimented. MH are blue shifted. This setup isnt. There is actually a lot of blue in the spectrum with these LEDs, it just doesn't visually dominate.

[moprint]

philbo32 are those the 21 or 38 led gu10? What size tank is that? Do you have a build thread on this setup? Sorry for all the questions just thinking of doing somenthing like this for a new nano tank that I am about to start. Thanks

[Altpers0na]

did you say that thing is 11 watts total?

[Gomer]

If you are asking me, that is 12 LEDs driven at about 2.5watts each, or 30watts total.

[Altpers0na]

actually i was looking at philbos, @ 9 x 1.2w

but i like yours at 30 also..

[liveforphysics]

Very nice work! Excellent choice of LED!

I have do some similar things with LEDs.

I use 28 cree XE-R blue emmiters thermal epoxy bonded to the bottom of my 12x54w T5 reflector.

I also use 12 cree XR-E Q4 (Q5's weren't released yet, currently I would choose the R2) on the nano tank I made for my ex-girlfriend, along with 6 XR-E high bin 460nm blue LEDs for coloring. It's never been a very sucessful for corals, dispite the tank appearing to be very bright (could also be her dreadful maintence...) I belive this to be because efficient LEDs do not produce spectrum below 460nm, which misses the 415-420nm spectrum required to stimulate Chloro A.

Cree makes the best LEDs in the world right now.

You can create the light output of the solaris LED lighting unit with 1/4th -1/6th the LEDs and use about 1/3rd the power by using modern high bin Cree LEDs vs Luxeons.

LED tech just became more efficient (for production power LEDs) than florecent and most MH this year. If they can get the spectrum low enough, it will make for very exciting LED lighting possibilitys for reef tanks.

Great Work!

-Luke

[Gomer]

Aren't Solaris users reporting good growth? I would put my $ on maintenance over the LEDs for your test tank. Also, you can use Royal Blue instead of Blue crees.

[Gomer]

Another comparison, this time in freshwater.

Again, all images are directly comparable. Exact same settings for all images

2x39 T5HO GE Starcoats
1x36watt AH Supply 6700k CoraLife
12x Cree XR-E (~30watts)

[allstar.h2o]

Gomer

Are these the same as your 12x Cree XRE Q5 bin? If so I think that I am in luck. I have two of these panels with 36 LED each. They are blinding to look at! I have been thinking about running 4 panels with a total 144 LED on a 29 gallon with one or two 24 in UVI actinic for some pop.

[Gomer]

I am 100% possitive those are not XR-E's, let alone Q bin. I think those might be Cree PLCC SMD LEDs. .
http://www.cree.com/products/ledlamps_plcc.htm

[allstar.h2o]

I have no idea. I have been researching them with out much luck. What do you think about them as reef lighting?

[Gomer]

here is one of the PLCC LEDs without the phosphor coating. It has 6 contacts and the 3 emitters in the same location as yours.

[Gomer]

Right now I am going through a few thermal checks. I did the 5min runtime and the heatsink was cool. on the 30min one right now (with all lights on)

what I did:
1) cut my cree light in half
2) removed my third light (nanotunners upgrade)
3) cut the reflector
4) installed 2 1" vents above the heatsink (i'll get photos later)
5) spliced in the driver to one of the PC power lines
6) sealed up most of the air flow by the fans and made both fans blow outward (this forces cool air in through the vents above the heatsink
7) test to make sure nothing catches on fire
8) bask in the glory of this wonderful little lighting upgrade.

Tank shots to come (albeit over a "sleeping tank with bleached corals) in an hour or so after it passes a longer term heat check.

[Gomer]

Comparison photos

Color representation is fairly accurate
The following is identical: Color Balance, Iso, Aperature, 1x 50/50 24watt PC, 1x actinic 24watt PC

Top: 6x Cree XR-E Q bin @ 700mA (~15watts), Shutter speed = 1/30
Middle: 1x 10,000K 24watt PC, Shutter speed = 1/30
Bottom: 6x Cree XR-E Q bin @ 700mA, Shutter speed = 1/50



The shimmer IMO is excellent when the hydor causes surface turbulence.
The color feels very natural. Not too yellow, not too blue (remember, the coral are bleached and recovering). You can easily get more blue blue by changing the 50/50 to an actinic.


Here are the 2 vents I added above the heatsink

[liveforphysics]

Early Solaris 24" LED lighting. 2 x 25 emmiter grids. The blue emmiters making 15lumens, the white 28-30lumens. Total output, 1200-1400lumens roughly.

Your modern LED setup. 6x Q5 bin Cree LEDs.

180 lumens x 6. 1080 lumens at only 15w. Very impressive!

It's a good thing that the solaris unit did make the "I4" upgrade, as it's only about 30% away from being as efficient as your DIY setup now.

Great Work!

[Gomer]

Thanks

This project finally payed off! I am tempted to get another bicube LOL



Other info that people will want to know:


Cost of project*

6x Cree XR-E Q-bin (7.75ea) $46.50
1x heatsink $20 (I only used 1/2 of mine, so you can probably get a 1/2 size one for $15
1x 700mA driver $30 (there are cheaper alternatives. This one can be driven with wall power and spliced directly to your AC PC cables)
thermal epoxy $7
Shipping summed $15

Total= $118.50

How much does a nanotuners PC upgrade cost?

*Assumes you have your own Dremel, soldering iron, heatshrink, screw driver or equivalents

[Flint&Eric]

gomer, these would work great for nice accent spots for those not wanting to replace their existing lighting.

[philbo32]

Originally posted by moprint
philbo32 are those the 21 or 38 led gu10? What size tank is that? Do you have a build thread on this setup? Sorry for all the questions just thinking of doing somenthing like this for a new nano tank that I am about to start. Thanks

They are 21 LED GU10s, the tank size is around 100 litres including the sump. I haven't made a build thread, I can take pics of the wiring any answer any questions you have if you want.

Phil

[philbo32]

Originally posted by Altpers0na
did you say that thing is 11 watts total?

Yup around 10.8 total wattage.

[Gomer]

Not trying to be rude, but since this is a documentation of a specific LED project and not an overview LED post, wouldn't it be better to keep your project in a dedicated thread?
(btw, 11 watts means little with LEDs till you know the lumen efficiency)